• Journal of Korea Water Resources Association
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• v.56 no.9
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• pp.543-551
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• 2023

Snow is an essential climate factor that affects the climate system and surface energy balance, and it also has a crucial role in water balance by providing solid water stored during the winter for spring runoff and groundwater recharge. In this study, statistical analysis of Local Data Assimilation and Prediction System (LDAPS), Modern.-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2), and ERA5-Land snow depth data were used to evaluate the applicability in South Korea. The statistical analysis between the Automated Synoptic Observing System (ASOS) ground observation data provided by the Korea Meteorological Administration (KMA) and the reanalysis data showed that LDAPS and ERA5-Land were highly correlated with a correlation coefficient of more than 0.69, but LDAPS showed a large error with an RMSE of 0.79 m. In the case of MERRA-2, the correlation coefficient was lower at 0.17 because the constant value was estimated continuously for some periods, which did not adequately simulate the increase and decrease trend between data. The statistical analysis of LDAPS and ASOS showed high and low performance in the nearby Gangwon Province, where the average snowfall is relatively high, and in the southern region, where the average snowfall is low, respectively. Finally, the error variance between the four independent snow depth data used in this study was calculated through triple collocation (TC), and a merged snow depth data was produced through weighting factors. The reanalyzed data showed the highest error variance in the order of LDAPS, MERRA-2, and ERA5-Land, and LDAPS was given a lower weighting factor due to its higher error variance. In addition, the spatial distribution of ERA5-Land snow depth data showed less variability, so the TC-merged snow depth data showed a similar spatial distribution to MERRA-2, which has a low spatial resolution. Considering the correlation, error, and uncertainty of the data, the ERA5-Land data is suitable for snow-related analysis in South Korea. In addition, it is expected that LDAPS data, which is highly correlated with other data but tends to be overestimated, can be actively utilized for high-resolution representation of regional and climatic diversity if appropriate corrections are performed.

• The Journal of Engineering Geology
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• v.33 no.3
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• pp.371-388
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• 2023

A stratum with a complex composition and a distributed low-permeability soil layer is difficult to remediate quickly because the soil remediation does not proceed easily. For efficient purification, the permeability should be improved and the soil remediation agent (H₂O₂) should be injected into the contaminated section to make sufficient contact with the TPH (Total petroleum hydrocarbons). This study analyzed a method for crack formation and effective delivery of the soil remediation agent based on pneumatic fracturing, plasma blasting, and vacuum suction (the PPV method) and compared its improvement effect relative to chemical oxidation. A demonstration test confirmed the effective delivery of the soil remediation agent to a site contaminated with TPH. The injection amount and injection time were monitored to calculate the delivery characteristics and the range of influence, and electrical resistivity surveying qualitatively confirmed changes in the underground environment. Permeability tests also evaluated and compared the permeability changes for each method. The amount of soil remediation agent injected was increased by about 4.74 to 7.48 times in the experimental group (PPV method) compared with the control group (chemical oxidation); the PPV method allowed injection rates per unit time (L/min) about 5.00 to 7.54 times quicker than the control method. Electrical resistivity measurements assessed that in the PPV method, the diffusion of H₂O₂2 and other fluids to the surface soil layer reduced the low resistivity change ratio: the horizontal change ratio between the injection well and the extraction well decreased the resistivity by about 1.12 to 2.38 times. Quantitative evaluation of hydraulic conductivity at the end of the test found that the control group had 21.1% of the original hydraulic conductivity and the experimental group retained 81.3% of the initial value, close to the initial permeability coefficient. Calculated radii of influence based on the survey results showed that the results of the PPV method were improved by 220% on average compared with those of the control group.

• Korean Journal of Ecology and Environment
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• v.56 no.1
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• pp.45-56
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• 2023

In stream ecosystem assessment, RIVPACS, which makes a simple but clear evaluation based on macroinvertebrate community, is widely used. In this study, a preliminary study was conducted to develop a RIVPACS-type model suitable for Korean streams nationwide. Reference streams were classified into two types(upstream and downstream), and a prediction model for macroinvertebrates was developed based on each family. A model for upstream was divided into 7 (train): 3 (test), and that for downstream was made using a leave-one-out method. Variables for the models were selected by non-metric multidimensional scaling, and seven variables were chosen, including elevation, slope, annual average temperature, stream width, forest ratio in land use, riffle ratio in hydrological characteristics, and boulder ratio in substrate composition. Stream order classified 3,224 sites as upstream and downstream, and community compositions of sites were predicted. The prediction was conducted for 30 macroinvertebrate families. Expected (E) and observed fauna (O) were compared using an ASPT biotic index, which is computed by dividing the BMWPK score into the number of families in a community. EQR values (i.e. O/E) for ASPT were used to assess stream condition. Lastly, we compared EQR to BMI, an index that is commonly used in the assessment. In the results, the average observed ASPT was 4.82 (±2.04 SD) and the expected one was 6.30 (±0.79 SD), and the expected ASPT was higher than the observed one. In the comparison between EQR and BMI index, EQR generally showed a higher value than the BMI index.

• The Journal of Korean Society for Radiation Therapy
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• v.34
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• pp.83-92
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• 2022

Purpose: To evaluate usefulness of Tomotherapy and Halcyon VMAT treatment in radiation therapy for bi-breast cancer Materials and Methods: For 10 patients with bi-breast cancer, volumetric modulated arc therapy(VMAT) treatment plan was established using helical Tomotherapy(Accuray. USA) with field width of 5.0-cm and pitch of 0.287, and Halcyon(Varian Medical System, Palo Alto, CA, Version 3.0 USA) of 6arc and 8arc. Prescribed dose was 42.4 Gy/16, and V _40.3Gy of Planning Target Volume(PTV) was 90%. The quality of plan was evaluated by comparing the dose to tumor and normal organs, and the efficiency was evaluated by comparing total MU and beam on time. Results: About three treatment plans(Tomotherapy, Halcyon 6Arc VMAT, Halcyon 8Arc VMAT) , the mean homogeneity index(H.I) of PTV were 1.07, 1.10, 1.11, and the mean conformity index(C.I) of PTV were 1.21, 1.16, 1.17, respectively. The average value of the dose assessment item for a normal organ is V _5Gy(%) of both lung was 36.3, 31.2, 29.7, and V _15Gy(%) were 18.6, 15.5, 14.6, respectively. The mean heart dose(Gy) were 4.17, 2.69, 2.51. Total MU were (7498.6, 2494.2, 2471.5), and beam on time(sec) were 462.5, 195.4, 198.0. Conclusion: Halcyon VMAT showed similar quality of treatment plan compared to helical Tomotherapy, while also protecting normal organs. In addition, the efficiency of radiotherapy increased due to a decrease in Beam On Time and MU.

• Journal of the Korean Orthopaedic Association
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• v.54 no.1
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• pp.30-36
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• 2019

Purpose: This study examined the effects of gender, age, underlying disease, duration after onset of symptoms, preoperative invasive procedures, bacterial culture of joint fluid, and stage of infection by the Gachter classification on the prognosis of patients with infectious knee arthritis who underwent arthroscopic surgery. Materials and Methods: From June 2014 to December 2016, 51 patients who underwent arthroscopic surgery for infective knee arthritis were enrolled in this study. The average follow-up period was 14.2±2.1 months (range, 12-20 months). The subjects were 27 men (52.9%) and 24 women (47.1%), with an average age of 55.1±17.6 years (range, 13-84 years). A preoperative evaluation of the joint aspiration with a count of more than 50,000 leukocytes and a polymorphonuclear leukocyte count of 95% or more was performed. All patients underwent arthroscopic surgery and postoperative continuous joint irrigation. Results: The initial mean value of the C-reactive protein decreased from 9.55±6.76 mg/dl (range, 1.51-31.06 mg/dl) to a final mean of 0.74±1.26 mg/dl (range, 0.08-6.77 mg/dl); the mean duration of C-reactive protein normalization was 27.6±18.9 days (range, 8-93 days). Among the 51 patients who received arthroscopic surgery and antibiotics, 44 patients (86.3%) with infectious knee arthritis completed treatment with improved clinical symptoms, such as fever, pain, and edema, and the C-reactive protein decreased to less than 0.5 mg/dl. Finally, 5 cases were treated with two or more arthroscopic operations, and 2 cases were converted to arthroplasty after prosthesis of antibiotic-loaded acrylic cement. Conclusion: The duration of surgery after the onset of symptoms and the stage according to the Gächter classification are important prognostic factors for predicting the successful treatment of infectious knee arthritis. On the other hand, the other factors were not statistically significant. Nevertheless, patients with bacteria cultured from the joint fluids appear to reflect the treatment period because the period of normalization of the C-reactive protein is shorter than that of the control group.

• Korea Science and Art Forum
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• v.21
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• pp.31-43
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• 2015

Information and Communications Technology (ICT) is one of the technologies which represent the core value of the creative economy. It has served as a vehicle connecting the existing industry and corporate infrastructure, developing existing products and services and creating new products and services. In addition to the ICT, new devices including big data, mobile gadgets and wearable products are gaining a great attention sending an expectation for a new market-pioneering. Further, Internet of Things (IoT) is helping solidify the ICT-based social development connecting human-to-human, human-to-things and things-to-things. This means that the manufacturing-based hardware development needs to be achieved simultaneously with software development through convergence. The essential element the convergence between hardware and software is OS, for which world's leading companies such as Google and Apple have launched an intense development recognizing the importance of software. Against this backdrop, the status-quo of the software market has been examined for the study of the present report (Korea Evaluation Institute of Industrial Technology: Professional Design Technology Development Project). As a result, the software platform-based Google's android and Apple's iOS are dominant in the global market and late comers are trying to enter the market through various pathways by releasing web-based OS and similar OS to provide a new paradigm to the market. The present study is aimed at finding the way to utilize a smart content by which anyone can be a developer based on OS responding to such as social change, newly defining a smart content to be universally utilized and analyzing the market to deal with a rapid market change. The study method, scope and details are as follows: Literature investigation, Analysis on the app market according to a smart classification system, Trend analysis on the current content market, Identification of five common trends through comparison among the universal definition of smart content, the status-quo of application represented in the app market and content market situation. In conclusion, the smart content market is independent but is expected to develop in the form of a single organic body being connected each other. Therefore, the further classification system and development focus should be made in a way to see the area from multiple perspectives including a social point of view in terms of the existing technology, culture, business and consumers.

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.249-255
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• 2023

Korean melon (Cucumis melo L.) is grown mostly in Northeast Asia area, and as a fruit mainly produced in Korea, the yield per unit area continues to improve, but the cultivation method is limited to soil cultivation, so it is necessary to develop hydroponic cultivation technology for scale and labor-saving is needed. As the ratio of NO₃^- increased, the plant height, the leaf length, the leaf width, and the internode length became longer and larger. On the other hand, the SPAD value decreased. The lower the ratio of NO₃^-, the faster the female flower bloom, and there was no difference in fruit maturity between treatments. There was no difference in the shape of fruit according to the ratio of NO₃^-, and the hardness was higher as the ratio of NO₃^- was lower. The total yield from March to July was KM3 5,650 kg/10a and KM1 4,439 kg/10a, 27% higher in KM3 and, in particular, 36% higher in quantity from March to May, when Korean melon prices were high season. Therefore, it was judged that it would be appropriate to supply NO₃^- suitable for hydroponic cultivation of Korean melon, which was formalized in December and produced from spring, at the level of 6.5 to 10 me·L^-1.

• Journal of Nutrition and Health
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• v.56 no.3
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• pp.315-329
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• 2023

Purpose: This study examined the meal-kit consumption practices of adults in their 20s and 30s and analyzed the properties that should be given priority for improvement among the selection attributes to improve the quality of meal-kits. Methods: Statistical analyses were conducted using the SPSS program (ver. 28.0) for χ²-test, t-test, one-way analysis of variance, Duncan's multiple range test, factor analysis, and Importance-Satisfaction Analysis (ISA). Results: Of the 249 subjects surveyed, 85.5% had some experience of purchasing meal-kits, with significantly more females than males (p < 0.01), significantly more married people than single people (p < 0.05), significantly more employed people than unemployed people (p < 0.05). Meal-kits were purchased most frequently for meals (60.6%), from discount stores or supermarkets (44.6%), and priced between 10,000 won and 20,000 won per person (46.9%). The overall satisfaction with meal-kits was 4.1 out of 5.0 points. The frequency of purchases was Korean soup dishes (69.5%), Korean main dishes (47.4%), and Korean street snacks (46.9%). Factor analysis of the meal-kit selection attributes revealed, 4 factors: 'quality of food,' 'packaging and diversity,' 'quality of meal-kit,' and 'convenience and price.' Compared to single-person households, multi-person households placed significantly higher importance on the 'quality of food,' 'packaging and diversity,' and 'quality of meal-kit.' The factor, 'packaging and diversity' were significantly higher in the importance evaluation scores for females (p < 0.01), married people (p < 0.05), and people in their 30s (p < 0.05) among meal-kit consumers. According to the ISA results, a critical aspect that meal-kit manufacturers or sellers should strengthen is 'price.' Conclusion: Meal-kit products will need to be developed for various purposes that offer high value for money that can satisfy the consumers' needs to improve the satisfaction of meal-kit consumers.

• Asia Marketing Journal
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• v.11 no.4
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• pp.95-119
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• 2010

Although there have been many studies regarding the inconsistency between consumers' attitudes and behavior, prior research has almost exclusively focused on the relationship between the attitude before behavior and the initial behavior. Relatively little research has been conducted on consumer satisfaction after purchase and post-purchase behavior. This research proposed that the relationship between satisfaction and post-purchase behavior is moderated by consumers' psychological characteristics such as need for cognitive closure(NCC) and temporal self-construal(SC). The need for cognitive closure refers to individuals' desire for a firm answer to a question and an aversion toward ambiguity. We assumed the need for cognitive closure as a major moderating variable because it is judged that the requirement for cognition clearly varies between when a consumer repurchases the same product and seeks a new alternative. Individuals who tend to end cognition due to time constraints or inappropriate conditions may display considerable cognitive impatience or impulsivity and has a higher probability in repurchasing the same product than a consumer without such limitations. They would avoid further consideration for new alternatives and the likelihood of the repurchase for prior alternative would increase. As hypothesized, significant moderating effect of the NCC was confirmed. This result gives a significant implication for a corporate to establish effective marketing strategies. For a corporate or product brand that has been occupying the market after entering the market earlier, it would be effective to maintain need for cognitive closure high in the existing consumers and thereby preventing the consumers from being interested in the new alternatives. On the other hand, new brands that have just entered the market need to lower the potential consumers' need for cognitive closure so that the consumers can be interested in new alternatives. Along with need for cognitive closure, temporal self-construal also turned out to moderate the satisfaction-repurchase. temporal SC reflects the extent to which individuals view themselves either as an individuated entity or in relation to others. Consumers under a temporarily independent SC would repurchase former alternative again according to their prior satisfaction and evaluation. In contrast, consumers in temporal interdependent SC tended to switch to a new alternative because they value interpersonal relationships above anything else and have a tendency to rely heavily on in-group opinions. When they are confronted with additional opinions, it is highly probable that he/she will choose a new product as an alternative. By proving the impact that temporal self-construal has on repurchasing behavior, this study is providing the marketers with new standards for establishing successful promotional strategies. For example, if the buyer and the user is the same for a product, it would be effective for the seller to convince the consumer to make decision subjectively by encouraging temporal independent self-construal. On the contrary, in the case where the purchase is made by an individual but the product is consumed by a group of people. For example, a housewife is more likely to choose the products or brands that her husband or children prefer rather than the ones that she likes by herself. In that case, emphasizing how the whole family can be satisfied and happy about the product would be effective for promoting repurchase.

• Korean Journal of Culture and Social Issue
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• v.18 no.2
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• pp.301-327
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• 2012

This study investigated body images based on the survey data drawn from college students in three East Asian countries(Korea, Japan, and China). 347 Korean, 341 Chinese, and 271 Japanese college students responded to questions designed to measure body images such as body-related values (operability, inclination, locus of evaluation, and instrumentality of appearance), body esteem (appearance, and health), and objectified body-consciousness ( surveillance and shame). The results showed that body images differ among countries. Regarding body-related values, Korean students have least conservative beliefs and followed by Japanese, and Chinese. Korean students showed the highest acceptance level for the voluntary body alteration(operability), highest inclination to body appearance over health. They also showed the strongest tendency of evaluating their body from the observer's point of view and the strongest belief about the social utility of body appearance compare to Japanese and Chinese students. Appearance- esteem of Korean was similar to Chinese but higher than Japanese. Surveillance and shame about body appearance of Korean students were similar to Japanese but higher than Chinese. Compare to male students, females showed stronger belief about the body appearance over health, lower appearance esteem, and higher surveillance and shame about body. Korean women showed the least conservative body-related values, and the levels of body appearance esteem and objectified body consciousness were located in between Japanese and Chinese women. Japanese women showed especially low body appearance esteem and highest surveillance and shame. Chinese women showed the most conservative body-related value, the highest appearance-esteem, and the lowest surveillance and shame. It was revealed that the body-related values indirectly affect to appearance-esteem through the mediating role of objectified body consciousness in Chinese and Japanese samples, but that the body-related values had direct effect on appearance-esteem as well in Korean sample.